Brighton's own character shapes the answer more than most neighbourhoods do. It is currently one of the most active new-build areas in the city, with a builder actively selling comparable new homes nearby, so a suite here is often competing against brand-new inventory rather than only against other resale listings.
Legal status decides whether the income counts for anything financially. A permitted secondary suite, meeting egress window, ceiling height and fire separation requirements confirmed by the City of Saskatoon, can be counted toward mortgage qualifying by a lender, while an unpermitted one cannot, regardless of the actual rent collected.
The real number for your specific Brighton property comes from comparable rentals in similar new-build inventory nearby. Get your hand-reviewed valuation from Joel Dyck.